Official

If you turn the faucet, water will always come out, but where does the water we are drinking come from?
On the Tokyo Metropolitan Waterworks Bureau's homepage, "Water Distribution System-Home Tap Water Information", select the ward municipal name, town name, and chome and press the search button to display the water purification plant that mainly distributes water. There is.

Let's try it.
When I entered all the street names in Chuo-ku, I found the following facts.

The area west of the Sumida River in Chuo-ku is mainly supplied from the Asaka Water Purification Plant. Water is taken from Arakawa. Arakawa also has a lot of water from the Tone River through the Musashi Channel.
The Asaka Water Purification Plant is the largest water purification plant in Tokyo, with a processing capacity of 1.7 million cubic meters / day, accounting for 1/4 of the total processing capacity of the Tokyo Waterworks Bureau. The Asaka Water Purification Plant is located in Asaka City, Saitama Prefecture, not in Tokyo. A raw water communication pipe is installed between the Higashimurayama water purification plant, and in addition to the water of the Tone River and Arakawa River, the water of the Tama River can be used.

The area east of the Sumida River in Chuo-ku is mainly supplied from Kanamachijosuijo. Water is taken from the Edogawa River (Tone River water system).
Kanamachijosuijo is the second largest water purification plant in Tokyo, with a processing capacity of 1.5 million cubic meters / day, accounting for 1/5 of the total processing capacity of the Tokyo Waterworks Bureau.

In the Edo period, water was distributed to the city of Edo through Kanda Josui and Tamagawajosui. With the progress of urbanization in Tokyo, dependent water systems have changed, and water exchanges have been carried out over a wider area. Dams and rivers in various parts of the Kanto region support drinking water in Tokyo.

I want to use water carefully.